As a method of producing an amorphous alloy ribbon to be used for a core or a magnetic shield material, a liquid quenching method is widely known. As a liquid quenching method, there are a single-roll method (for example, see Japanese Patent No. 3494371), a twin-roll method (for example, see Japanese Patent Application Laid-Open (JP-A) No. H03-18459), a centrifugation method, or the like, and considering productivity or maintainability, a single-roll method is superior, by which a molten alloy is supplied through a molten metal nozzle to a surface of a rotating chill roll, and solidified by quenching to yield an amorphous alloy ribbon.
By a single-roll method, a ribbon is produced by forming a reservoir of a molten alloy (also known as a “puddle”) with a chill roll surface and a molten metal nozzle, and consequently a broad ribbon can be produced favorably.